This page gives an overview of Signalling on the Welsh Highland Railway.
- Main Article: NWNGR Signalling
The North Wales Narrow Gauge Railways line from Dinas Junction to Rhyd Ddu was signalled conventionally for its time. There were signal boxes at Dinas, Tryfan Junction and Waunfawr and probably other locations too. It was equipped with semaphore signals. Even the small station at Snowdon Ranger at one time had at least one semaphore signal.
Signalling on the modern WHR
The signalling on the WHR is much simpler than that used on the Ffestiniog Railway.
In order to enter any section of line, the train crew must obtain permission from Control and the relevant token. Each section of line is a token block section. The WHR uses the traditional Staff and Ticket system in which trains can either be issued with the section staff or a numbered ticket. Tickets allow multiple trains to pass one-at-a-time through a section in one direction. The Controller advises the train crew which method they will be using. Tickets are kept in a locked box opened by a key on the staff. This means the last train must use the staff to pass through the section, so it can be used for trains to travel in the opposite direction. For additional protection, both the footplate crew and the guard must see the token or ticket before the train can depart. The staffs are all coloured differently to help distinguish them. The metal tokens are similarly coloured.
The majority of the points at passing loops are operated automatically using the Automatic Train Operated Trailable (ATOTP) system, rather than a manually operated lever or point motor. Instead of traditional signals to indicate that a train can enter a section or station stop boards are used instead. The stop board design is based on the old FR Disc Signals. BR stop boards normally have a small red circle and the word "Stop", the WHR design instead has a large red circle with a ring of black dots in order to resemble FR discs. Those signals which use lights to give a proceed indication have the lights positioned in place of the top and bottom most dots. The appearance of these signals has led to them sometimes being called "ladybird" signals.
At some stations a "Shunt" token is used to allow shunting to take place (such as a locomotive running round a train). They are provided at Dinas, Rhyd Ddu, Beddgelert and at Pont Croesor. The shunt token can only be withdrawn (used) with permission from Control and if there are no trains approaching the station in the adjacent single line sections. Withdrawing the token causes the two yellow lights to go out on the home board on the line approaching the station, preventing other trains from entering the station. Stations without shunt tokens have no home boards. Where sidings exist the points can be unlocked with a key on the staff.
The table shows the boards/signals passed by a train as it leaves a section and passes a station in the order they are passed.
|Fixed Distant||States that a station is being approached and that the driver must be prepared to stop at the home board.|
|Home board||A stop board with orange proceed indicator lights. The lights will not illuminate if the shunt token for the station has been withdrawn.|
|Point indicator light||Shows that the trailable points are fully over. If this light is out the train must stop whilst the points are secured in position.|
|Section board||A notice at the start of the platform marking the end of the section, usually reads "End of Section, Permissive Platform, Proceed as Far as Platform Line is Clear"|
|Stop board||A stop board at the end of the platform (where there might otherwise be a starting signal) with associated notice: "Obtain token and permission to proceed".|
Cae Pawb – The Cambrian crossing
Cae Pawb is at the north-western end of the Network Rail Harlech to Porthmadog signalling section, which is controlled from Machynlleth Control Centre. Standard gauge trains are protected by signals and wide-to-gauge trap points on the WHR line, which are interlocked with the standard gauge ERTMS signalling. The crossing is activated locally and ERTMS automatically gives permission for WHR trains to cross provided the standard gauge section is available. A crossing controller operates the crossing when passenger trains are running, with operation at other times being carried out by the train crew.
A set of replica white wooden crossing gates separate the narrow gauge line from the standard gauge track and continue the Network Rail boundary fencing. They are left open when a crossing controller is present. The gates open inwards to prevent them blocking the standard gauge line. A replica signal box was constructed for this crossing but has now been installed at Pen y Mount to control the junction with the Welsh Highland Heritage Railway.
The signals at Cae Pawb are colour light signals. They were originally "ladybird" signals similar to home boards but were changed in order to give a clearer indication.
The future: Resignalling and micro-ETS
One of the disadvantages of the staff and ticket system is that it is very inflexible. If a locomotive fails in a station, for example, a token staff may be at the wrong end of a section and will have to be moved by road. This situation does not occur under the Electric Train Staff (ETS) system, a more advanced system in which tokens can be obtained at either end of a section from a token instrument.
ETS has been used on the Ffestiniog Railway for many years and the FR Co. were anxious to obtain enough ETS instruments to equip the WHR. After a long search, sufficient ETS equipment to operate the entire railway has been obtained from the Irish railway company Iarnród Éireann. The equipment became redundant after Iarnród Éireann recently modernised its signalling systems.
As the WHR has no telephone cabling to connect the system, the FR Co. is developing a more modern alternative method of connecting the ETS machines. Until the system is finished, the WHR will continue using its current token systems. This new system obviates the need for telegraph lines by connecting the machines through the internet. This has led to the term "micro-ETS being coined.
Resignalling is taking place in the winter of 2017/18. The plan is to upgrade signalling and standardise the layouts at stations, improving both saftey and flexibility. All signals will be of the ladybird-type with a light at the top and the bottom - similar to the existing home boards but with the ability to show a danger aspect by lighting up red. All stations will be equipped with starting signals which will operate along the principle at Tanygrisiau; the signal will only clear when the appropriate token is inserted into a keyswitch below. All stations will now be equipped with home signals and shunt tokens. In addition to this, there will be a "Train Approaching" indicator which is illuminated when the outer treadles (in advance of the fixed distant) are activated. When this is illuminated, the shunt token may not be withdrawn. This allows the shunt token to be withdrawn even if the adjacent sections are occupied. Signals will be returned to danger by the operation of treadles. This scheme will be compatible with micro-ETS.
- "Engineering the Welsh Highland Railway re-build". RailwayPeople.com. 15 August 2008. Retrieved 27 September 2008.
- "FR Company Information Release, 30.08.08". FR. 30 August 2008. Retrieved 30 August 2008.